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RinTinTigger
05-07-2010, 09:37 AM
Hey folks,

ive been asked a lot, how to calibrate your battery, to get more life out of it...

Calibrate your Battery

Calibrate the battery by completely draining it until the phone completely shuts itself off.
Turn the phone on again and let it shut itself off one more time.
Then charge your phone while it is off for over 8 hours.
This will fully charge the battery so that when the Android is turned on, it now sees the battery as full.

It is recommended to repeat this process at least one more time.

You should see a significant increase in your battery’s charge life.

Calibration of a battery can be done at any point and a maintenance calibration is recommended every month.


RECALIBRATION:

A recalibration is mostly needed, when dealing with different kernels (ROOT!). Most custom recovery images provide the option "battery stats wipe" under the menue "Wipe".

Here is how ya do it!

1. Enter Recovery Mode
2. do a full nandroid (or nandroid+ext) backup
3. Enter "Wipe"-Menue
4. do "Battery stats wipe"
5. reboot

Then you just take the steps from a bove to continue:

Calibrate the battery by completely draining it until the phone completely shuts itself off.
Turn the phone on again and let it shut itself off one more time.
Then charge your phone while it is off for over 8 hours.
This will fully charge the battery so that when the Android is turned on, it now sees the battery as full.

It is recommended to repeat this process at least one more time.

You should see a significant increase in your battery’s charge life.

Calibration of a battery can be done at any point and a maintenance calibration is recommended every month.


Tigger

:oilleak:

sliceburgslim
05-07-2010, 10:42 AM
Nice! I should do this with all the kernel flashing I do. Thanks for posting!

rensky
05-07-2010, 02:33 PM
has anyone done this and has anyone seen a difference?

NeonMonster
05-07-2010, 09:17 PM
has anyone done this and has anyone seen a difference?

This is general battery care and they recommending doing it for any device that has a battery.

I've never done it with my Nexus however, because I can't leave the device turned off for that long and not use it! X__X

GandJim
05-10-2010, 01:56 AM
Calibrate the battery by completely draining it until the phone completely shuts itself off.
Turn the phone on again and let it shut itself off one more time.
I'm a perfect dummy concerning all these things and must say I'm a little bit scared to do this. Isn't there a risk of losing some information? Time and date is the first thing that comes to my mind, but maybe also some other more technical data I haven't a clue of what they mean?

I have another phone which I put aside for months (if not years). When I tried to recharge it again to lend it to a visiting friend, it just doesn't work anymore. I changed the battery, but the phone stays dead (or more precisely the screen stays dead). No idea what the problem is. Maybe it's nothing relating to the battery and didn't bother to find out, as it's a cheap phone, but would be devastated if it happens to my Nexus.

Jim

venki5star
05-10-2010, 03:43 AM
Thanks. I tried this with no faith. But I could see a vast different after the first calibration. Thanks to the poster.

floh
05-10-2010, 03:46 AM
I'm a perfect dummy concerning all these things and must say I'm a little bit scared to do this. Isn't there a risk of losing some information? Time and date is the first thing that comes to my mind, but maybe also some other more technical data I haven't a clue of what they mean?

There should not be any problems, as for the clock etc. there is another power source and all other data will be stored on the flash memory (which does not need power to store it's data – at least for some months).

Just think about it, you can easily take out the battery of your phone (e.g. before you send it in for service) and won't lose data.

dd4005
05-10-2010, 04:12 AM
I'm surprised this would be necessary with a Lithium (-Ion or -Polymer) battery. This is the kind of procedure that goes back to the days of NiCad and NiMH batteries that suffered from the memory effect.

Saying that though, I'm going to try it.

tonybhoy
05-10-2010, 05:48 AM
to add to the o/p,when your phones battery runs down and you get the black screen press and hold power buttond and trackball till you get the bootlogging screen(white)just leave your n1 sitting on that for a while and it will drain the rest of the juice out of the battery,don't panic when going to charge it and you don't get the orange light as it takes a bit of time for it to charge itself up so best leave it over night,i do this once a month and notice a decent change in battery life:)

jah
05-10-2010, 08:26 AM
I've heard that this is unnecessary and can damage the battery. Are we sure this is a good idea?

RinTinTigger
05-11-2010, 07:31 AM
Calibrate the battery by completely draining it until the phone completely shuts itself off.
Turn the phone on again and let it shut itself off one more time.
I'm a perfect dummy concerning all these things and must say I'm a little bit scared to do this. Isn't there a risk of losing some information? Time and date is the first thing that comes to my mind, but maybe also some other more technical data I haven't a clue of what they mean?

I have another phone which I put aside for months (if not years). When I tried to recharge it again to lend it to a visiting friend, it just doesn't work anymore. I changed the battery, but the phone stays dead (or more precisely the screen stays dead). No idea what the problem is. Maybe it's nothing relating to the battery and didn't bother to find out, as it's a cheap phone, but would be devastated if it happens to my Nexus.

Jim

Its no problem to do this with your Nexus, it wont let you lose any data or anything, at least the frist step called "Calibration"

sliceburgslim
05-11-2010, 08:07 AM
Ive heard that draining li-ion batteries down to zero can be bad for the battery over time...

RinTinTigger
05-11-2010, 10:12 AM
Ive heard that draining li-ion batteries down to zero can be bad for the battery over time...

Lithium Ion batterys are NOT damaged by fully unload!
But its in your hands, you dont have to follow my directions.

Ive been using this howto now since i have the nexus one and been using it for 6 months on my milestone!

no problems so far =)

sliceburgslim
05-11-2010, 10:54 AM
Read the section on discharging here

[Guide] Everything you wanted to know about Li-Ion batteries but were afraid to ask! - xda-developers (http://forum.xda-developers.com/showthread.php?t=669497)

Still think it does not harm your battery over time?

sliceburgslim
05-11-2010, 11:19 AM
Seems to me that this method of yours is good for the phone...bad for the battery IMO

mattanonymous
05-11-2010, 04:47 PM
The only thing this does is calibrates the battery charge sensing hardware/software.

In general allowing a Li-ion battery to go below half a full charge is not good for the life of the battery.

I'd rather look at 50% as my new 'empty'. In addition to not needlessly damaging the battery, it also greatly reduces my concern for pinpoint accuracy when it comes to metering the charge.

CPMajai
05-11-2010, 06:51 PM
Seems to me that this method of yours is good for the phone...bad for the battery IMO

I agree. That's why I only did this method once. My battery meter seems to be more accurate now.

Doing some research (and by that i mean google) and you all will see that a complete depletion of Li-ion cells actually harm the capacitance of the cells. They roughly have about 250-300 charge cycles. So as long as you don't go through the entire deplete-recharge (100% to 0% to 100%) cycle, you're actually prolonging the battery life in the long run.

jimbobalu
05-12-2010, 12:45 PM
Is the calibration data stored in the battery or N1? I have 3 batteries and if it is stored in the N1 then this will not help me unless it remembers each batteries calibration data.

Thanks

Dalamar
05-13-2010, 08:13 PM
I know that Li-ion batteries generally shouldn't be run down if one can help it (and leaving them depleted state for an extended time can ruin them), but this procedure made a noticeable difference for my Nexus One, at least as far as giving a better indication of true charge remaining.

I'll admit, I didn't follow the recommended charging procedure when I first got my N1. I was too excited and so popped the battery in right away and booted it up before the initial charging.

Anyway, yesterday I ran the phone down completely playing long YouTube videos until it shut itself off. I turned it back on and ran it again until it did another auto-shutdown. Then I restarted in the boot loader until that conked out. By then it was well and truly out of juice and wouldn't start up at all.

After that I charged it overnight (a good 12 hours). Today I've noticed considerably better battery life. Now, I realize this is probably just a result of the software calibration having been thrown off initially when I didn't follow instructions and not an actual increase in available power, but it's nice to have a more accurate reading of true capacity remaining nonetheless.

It's not something I'd probably do often, because of the wear full cycling incurs on Li-ion cells, but it did seem to make a difference.

N1David
05-20-2010, 08:29 PM
I did this and notice no change in my battery life. Even still, the green light comes on when charging and it is not fully charged according to both the battery indicator on the screen lock and this app I have installed "Battery Status Pro". More so, the battery display on the lock screen reads 100% but I still have the charging indicator in the battery on my task bar.

chylife
07-12-2010, 10:24 AM
You don't do the battery calibration on Lithium-Ion and Lithium Polymer batteries. It won't help better, it is unnecessary.

dd4005
07-12-2010, 10:45 AM
You don't do the battery calibration on Lithium-Ion and Lithium Polymer batteries. It won't help better, it is unnecessary.
It does help. It doesn't make any difference what type of battery you've got, it helps to calibrate the battery monitor's idea of how much you've got remaining. It doesn't do anything to help the battery live longer - only the perception that it's living longer.

NiMH and NiCad batteries on the other hand, they do benefit from a full to empty discharge. With them, it's the actual battery that will perform better.

sliceburgslim
07-24-2010, 09:40 AM
Do NOT charge or plug in cable until your battery signals warning LOW sign. Then charge it to full.


Actually from what I've read, its not good to let the battery drain completely before Charging. Its better to charge around 40%-30%

Discharging your LIB fully (or less than 2.4 Volt per cell) is bad for the battery. Every time you do that, it can be said that small part of your battery (some cells) dies (they forever lose their charge). Do not store your batteries depleted, there's a high chance they will die completely or will become very "weak".

jah
07-24-2010, 11:14 AM
Try this:
Always charge your battery to full and THEN ONLY pluck the cable out, i.e. you must full charge you machine before you remove your cables.
Do NOT charge or plug in cable until your battery signals warning LOW sign. Then charge it to full.
If you use your computer always on cables, try to use it on battery 3 days until it empties, and then recharge it to full.
Keep you battery clean.
NOTE: It cannot be calibrated more than to it's factory setting.
3 days? hah!

alphawave7
07-24-2010, 02:28 PM
Do NOT charge or plug in cable until your battery signals warning LOW sign. Then charge it to full.


Actually from what I've read, its not good to let the battery drain completely before Charging. Its better to charge around 40%-30%

Discharging your LIB fully (or less than 2.4 Volt per cell) is bad for the battery. Every time you do that, it can be said that small part of your battery (some cells) dies (they forever lose their charge). Do not store your batteries depleted, there's a high chance they will die completely or will become very "weak".

Normal usage will not drain any Li-poly cell into this danger zone...only storing a dead cell for lengthy times, or intentionally draining/shorting the cell (or simple age/exhaustion) will get the cell into this danger zone. There is nothing wrong whatsoever with allowing your phone to shut itself off before a recharge...the charge algorithm shuts off the cell well before it reaches the danger zone, as a specification of the cell technology.

ellesshoo
07-24-2010, 02:50 PM
Do NOT charge or plug in cable until your battery signals warning LOW sign. Then charge it to full.


Actually from what I've read, its not good to let the battery drain completely before Charging. Its better to charge around 40%-30%

Discharging your LIB fully (or less than 2.4 Volt per cell) is bad for the battery. Every time you do that, it can be said that small part of your battery (some cells) dies (they forever lose their charge). Do not store your batteries depleted, there's a high chance they will die completely or will become very "weak".

Normal usage will not drain any Li-poly cell into this danger zone...only storing a dead cell for lengthy times, or intentionally draining/shorting the cell (or simple age/exhaustion) will get the cell into this danger zone. There is nothing wrong whatsoever with allowing your phone to shut itself off before a recharge...the charge algorithm shuts off the cell well before it reaches the danger zone, as a specification of the cell technology. This is correct, there is a monitor that will shut the thing down before you drop below the threshold voltage per cell. There is nothing wrong with letting your battery drain to shutoff. Just don't do it and then store it like that for a long time.

Fury
07-25-2010, 09:09 AM
No one has mentioned overcharging,
as a (bad) habit of mine, i like to drop my N1 on to the dock every time i get back to my room.

Im assuming this kills the battery aswell, as with laptops?

dd4005
07-25-2010, 11:55 AM
No one has mentioned overcharging,
as a (bad) habit of mine, i like to drop my N1 on to the dock every time i get back to my room.

Im assuming this kills the battery aswell, as with laptops?I'm guilty of this too. My phone will sometimes stay in it's dock for 3 days. When I take it out of the dock (after a whole day of being in) I'll find that although I earlier saw it had reached 100%, it later starts going down. It's usually about 97% when I take it out of dock.

tyler.durden
07-25-2010, 12:04 PM
The Li ion batteries in any consumer product such as a phone, PDA, mp3 player, laptop computer, digital camera, etc., have a circuit inside the battery package that controls charge and discharge of the actual Li ion cell. The circuit prevents overcharging and deep discharging, therefore there is no harm in running the phone until it shuts itself off and there is no harm in connecting it to the charger before the phone has shut itself off due to a low battery charge.

All this nonsense about overcharging and deep discharging that keeps getting repeated ad nauseum applies to the Li ion cells to which you have no direct access to in a consumer device. People who build model airplanes and robots buy Li ion cells to power them and must carefully monitor charging and especially discharging of the batteries in order to maximize their life and minimize the risk of a crash due to premature cell failure. They buy the raw Li ion cells without a built in protective circuit because they want to be able to charge and especially to discharge the cells very quickly, and a protective circuit built into the cell would prevent that.

keyplyr
07-25-2010, 02:27 PM
I've heard that this is unnecessary and can damage the battery. Are we sure this is a good idea?


Ive heard that draining li-ion batteries down to zero can be bad for the battery over time...



Discharging your LIB fully (or less than 2.4 Volt per cell) is bad for the battery. Every time you do that, it can be said that small part of your battery (some cells) dies (they forever lose their charge). Do not store your batteries depleted, there's a high chance they will die completely or will become very "weak".
Exactly

When I asked him last week, my student (who developed the Snapdragon processor at Qualcomm) thinks it is a very bad idea to completely drain the N1 battery in a vain attempt to "calibrate" the battery. He says there is no such thing as "calibrating" the battery and thinks these people are just attempting to sound knowledgeable when in fact they don't understand what they are talking about.

Krew
07-25-2010, 03:08 PM
You guys, why would the battery damage if the phone turns off? I mean come on, they are meant to be either on or off! NO amount of data can convince me that turning off my phone kills the battery. If it did kill the battery, there would be no on/off button!

alphawave7
07-25-2010, 05:37 PM
You guys, why would the battery damage if the phone turns off? I mean come on, they are meant to be either on or off! NO amount of data can convince me that turning off my phone kills the battery. If it did kill the battery, there would be no on/off button!

This is normal use, no damage to the battery can result from turning off the phone, allowing the phone to turn itself off,etc. It actually takes deliberate 'abuse' to damage your battery, so quit worrying. :)

alphawave7
07-25-2010, 05:44 PM
I've heard that this is unnecessary and can damage the battery. Are we sure this is a good idea?


Ive heard that draining li-ion batteries down to zero can be bad for the battery over time...



Discharging your LIB fully (or less than 2.4 Volt per cell) is bad for the battery. Every time you do that, it can be said that small part of your battery (some cells) dies (they forever lose their charge). Do not store your batteries depleted, there's a high chance they will die completely or will become very "weak".
Exactly

When I asked him last week, my student (who developed the Snapdragon processor at Qualcomm) thinks it is a very bad idea to completely drain the N1 battery in a vain attempt to "calibrate" the battery. He says there is no such thing as "calibrating" the battery and thinks these people are just attempting to sound knowledgeable when in fact they don't understand what they are talking about.





I think you (and he) misunderstand the intent behind draining and fully recharging a cell...we're not trying to 'calibrate' the battery per se, we're calibrating the phone's charging algorithm to the cell's depletion and peak voltage readings so the meter reports a more accurate representation of cell charge state. It's a diagnostic 'tool' when troubleshooting battery issues, and can rule out a misreading meter as a culprit when troubleshooting cell issues. This recalibration has NO impact on cell performance itself.

keyplyr
07-25-2010, 08:33 PM
I've heard that this is unnecessary and can damage the battery. Are we sure this is a good idea?





Discharging your LIB fully (or less than 2.4 Volt per cell) is bad for the battery. Every time you do that, it can be said that small part of your battery (some cells) dies (they forever lose their charge). Do not store your batteries depleted, there's a high chance they will die completely or will become very "weak".
Exactly

When I asked him last week, my student (who developed the Snapdragon processor at Qualcomm) thinks it is a very bad idea to completely drain the N1 battery in a vain attempt to "calibrate" the battery. He says there is no such thing as "calibrating" the battery and thinks these people are just attempting to sound knowledgeable when in fact they don't understand what they are talking about.





I think you (and he) misunderstand the intent behind draining and fully recharging a cell...we're not trying to 'calibrate' the battery per se, we're calibrating the phone's charging algorithm to the cell's depletion and peak voltage readings so the meter reports a more accurate representation of cell charge state. It's a diagnostic 'tool' when troubleshooting battery issues, and can rule out a misreading meter as a culprit when troubleshooting cell issues. This recalibration has NO impact on cell performance itself.
I think the dynamic here is - do not completely drain the battery for *any* reason.

alphawave7
07-25-2010, 08:53 PM
I think the dynamic here is - do not completely drain the battery for *any* reason.

I reiterate-allowing the phone discharge to shut itself off is not 'completely draining' the battery..and falls under normal usage. It requires deliberate circumvention/neglect to completely drain the cell into the danger zone. As has been described above, there is a valid reason to discharge the cell to recalibrate the phone's charge reporting meter, especially when coupled with a full recharge after discharge. This results in the most accurate charge-state reporting by the phone.

keyplyr
07-25-2010, 09:05 PM
Well, I think I'll follow the advice of a senior project developer at Qualcomm when he says not to do this :)

Google sends a plane for this guy when Qualcomm loans him out for consultation and he's been to HTC in Tawain many times. I'd think he'd know what's BS and what's not.

alphawave7
07-25-2010, 09:09 PM
Well, I think I'll follow the advice of a senior project developer at Qualcomm when he says not to do this :)

Google sends a plane for this guy when Qualcomm loans him out for consultation and he's been to HTC in Tawain many times. I'd think he'd know what's BS and what's not.




I take offense to your suggestion I'm spreading FUD/BS. You are free to believe as you wish.

keyplyr
07-25-2010, 09:15 PM
Well, I think I'll follow the advice of a senior project developer at Qualcomm when he says not to do this :)

Google sends a plane for this guy when Qualcomm loans him out for consultation and he's been to HTC in Tawain many times. I'd think he'd know what's BS and what's not.




I take offense to your suggestion I'm spreading FUD/BS. You are free to believe as you wish.
Since you've chosen to take this personally (which it was not) you're also free to take offense as you wish :)

aseems
07-26-2010, 07:41 AM
Originally Posted by AndroidIsTheTruth
"Yes I never let my battery drain less than 30% and only let it get that low if I'm in a situation where I'm not near a charger. At that point if it's before 20-15% I just shut it off."

1> • Discharging your LI Battery fully (or less than 2.4 Volt per cell) is bad for the battery. Every time you do that, it can be said that small part of your battery (some cells) dies (they forever lose their charge). Do not store your batteries depleted, there's a high chance they will die completely or will become very "weak".

2>• Worst LI Battery treatment is to keep it at 100% charge level at high temperature (think laptop/phone under direct sunlight, like car dashboard).

3> • Best LI Battery treatment, or LIBattery's "favorite" charge level - 40%. That's also the usual charge level you buy them with.

4> LIBs like frequent partial charges/discharges more than they like full charges/discharges.

Fury
08-04-2010, 07:25 AM
I just found this:
What is your battery life on Nexus One? - Android Help (http://www.google.com/support/forum/p/android/thread?tid=2eb4a163b4e3a6ff&hl=en)

Ry Guy, a google employee, linking to a thread that says its good to 100% discharge your battery.

Thoughts?

aseems
08-04-2010, 08:18 AM
Thanks Fury

I'm flummoxed....

I'm also confused ...

Ry Guy Quotes

"Discharge phone until it won't turn on (red LED is showing), then recharge until the LED is green. Leave it like that for two hours. (Make sure the phone is on when you start the recharging process)."

How???????? do i Make sure that the phone is on when i start the recharging process if it won't turn on???

I AM HIGHLY CONFUSED AND UNNERVED!

Fury
08-04-2010, 10:42 AM
I AM HIGHLY CONFUSED AND UNNERVED!

for the moment, im going to stick with what im doing right now, keep my N1 from hitting 0%, and try not to overcharge.

Even with the facts, i doubt i would change my routine extravagantly , too much of a hassle for me (being a lazy bum :bike4_smilie:)

aseems
08-04-2010, 11:48 AM
:( Fury
Need some light...

AndroidIsTheTruth?
Beer Goggles?
Wera?
Anyone?

sliceburgslim
08-04-2010, 05:17 PM
Thanks Fury

I'm flummoxed....

I'm also confused ...

Ry Guy Quotes

"Discharge phone until it won't turn on (red LED is showing), then recharge until the LED is green. Leave it like that for two hours. (Make sure the phone is on when you start the recharging process)."

How???????? do i Make sure that the phone is on when i start the recharging process if it won't turn on???

I AM HIGHLY CONFUSED AND UNNERVED!

Why not just turn the phone back on Once you have plugged it into the Charger?

aseems
08-04-2010, 09:45 PM
Thank you slim, but is this methodology for extending battery life correct?

WERA689
08-05-2010, 01:20 AM
Thank you slim, but is this methodology for extending battery life correct?


I tend to think not, to be honest. In my experience, simple normal usage and recharging before the phone goes dead seems to be the best for LiIon batteries. But hey, what do I know? :dance:

alphawave7
08-05-2010, 01:54 AM
"However, a full discharge/charge will reset the digital circuit of a 'smart' battery to improve the state-of-charge estimation"

Source: Charging lithium-ion batteries (http://www.batteryuniversity.com/partone-12.htm)


"Manufacturers rate the lithium-ion battery at an 80% depth of discharge. Repeated full (100%) discharges would lower the specified cycle count. It is therefore recommended to charge lithium-ion more often rather than letting it discharge down too low. Periodic full discharges are not needed because lithium-ion is not affected by memory."

Note in particular, the last sentence refers to full discharge with intent to override 'memory effect' as seen in NiCd/Nimh cells..Li-Ion cells suffer virtually no 'memory effects' by charge behaviour, so routine full discharge serves no purpose other than reducing overall charge cycle longevity. Insofar as charge frequency suggested, most of us are charging daily, which is plenty 'more often'.

Source: Discharge Methods (http://www.batteryuniversity.com/partone-16.htm)

"A lithium-ion battery provides 300-500 discharge/charge cycles. The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible. Instead, charge the battery more often or use a larger battery. There is no concern of memory when applying unscheduled charges.

Although lithium-ion is memory-free in terms of performance deterioration, batteries with fuel gauges exhibit what engineers refer to as "digital memory". Here is the reason: Short discharges with subsequent recharges do not provide the periodic calibration needed to synchronize the fuel gauge with the battery's state-of-charge. A deliberate full discharge and recharge every 30 charges corrects this problem. Letting the battery run down to the cut-off point in the equipment will do this. If ignored, the fuel gauge will become increasingly less accurate. (Read more in 'Choosing the right battery for portable computing', Part Two.)"

This suggests a full discharge and recharge is a great first step to troubleshooting charging or duration issues, which is why I suggest doing it first. All we can rely upon is actual duration before shutdown, and what the meter tells us is occurring...it's important that the meter be reporting capacity accurately before prejudicing your observed results.

Source: How to prolong lithium-based batteries (http://www.batteryuniversity.com/parttwo-34.htm)

aseems
08-05-2010, 05:04 AM
Source: Charging lithium-ion batteries (http://www.batteryuniversity.com/partone-12.htm)

Source: Discharge Methods (http://www.batteryuniversity.com/partone-16.htm)

Source: How to prolong lithium-based batteries (http://www.batteryuniversity.com/parttwo-34.htm)

Thank you Sir! :thank_you2:

I will keep my Battery between 30 & 50%
and then full discharge normally to shutdown for calibration, OCCASIONALLY (i.e. When the Occasion demands it :)

Fury
08-07-2010, 11:44 AM
There is so much ignorance in this thread it hurts.

If you don't have a clue what you're talking about, keep your mouth shut.

Yea, thanks for contributing, your helping ever one out here.

aseems
08-07-2010, 12:24 PM
There is so much ignorance in this thread it hurts.

If you don't have a clue what you're talking about, keep your mouth shut.

Thank you for your input!
bmn111
:slow:

Beer Goggles
08-07-2010, 01:02 PM
I've switched to using an atomic power cell.

Pros:
Never need to recharge.

Cons:
Need to wear a radiation suit whenever in the same building as the phone.

:dance:

dd4005
08-07-2010, 01:59 PM
"However, a full discharge/charge will reset the digital circuit of a 'smart' battery to improve the state-of-charge estimation"

Source: Charging lithium-ion batteries (http://www.batteryuniversity.com/partone-12.htm)


"Manufacturers rate the lithium-ion battery at an 80% depth of discharge. Repeated full (100%) discharges would lower the specified cycle count. It is therefore recommended to charge lithium-ion more often rather than letting it discharge down too low. Periodic full discharges are not needed because lithium-ion is not affected by memory."

Note in particular, the last sentence refers to full discharge with intent to override 'memory effect' as seen in NiCd/Nimh cells..Li-Ion cells suffer virtually no 'memory effects' by charge behaviour, so routine full discharge serves no purpose other than reducing overall charge cycle longevity. Insofar as charge frequency suggested, most of us are charging daily, which is plenty 'more often'.

Source: Discharge Methods (http://www.batteryuniversity.com/partone-16.htm)

"A lithium-ion battery provides 300-500 discharge/charge cycles. The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible. Instead, charge the battery more often or use a larger battery. There is no concern of memory when applying unscheduled charges.

Although lithium-ion is memory-free in terms of performance deterioration, batteries with fuel gauges exhibit what engineers refer to as "digital memory". Here is the reason: Short discharges with subsequent recharges do not provide the periodic calibration needed to synchronize the fuel gauge with the battery's state-of-charge. A deliberate full discharge and recharge every 30 charges corrects this problem. Letting the battery run down to the cut-off point in the equipment will do this. If ignored, the fuel gauge will become increasingly less accurate. (Read more in 'Choosing the right battery for portable computing', Part Two.)"

This suggests a full discharge and recharge is a great first step to troubleshooting charging or duration issues, which is why I suggest doing it first. All we can rely upon is actual duration before shutdown, and what the meter tells us is occurring...it's important that the meter be reporting capacity accurately before prejudicing your observed results.

Source: How to prolong lithium-based batteries (http://www.batteryuniversity.com/parttwo-34.htm)
Or in other words ... everything I said :rofl3::rofl3::rofl3:

Fury
08-30-2010, 09:08 AM
Interesting article i found:
Keep your charge on -- how to improve battery life on your Android phone | Android Central (http://www.androidcentral.com/keeping-your-charge-how-improve-battery-life-your-android-phone)

Every once in a while, it's fine to let the phone run down the whole way and then recharge. This helps keep the battery meter and the battery's actual memory on the same page and give a more accurate reading for battery life. If you're the geeky type and have rooted your phone, you can delete /data/system/batterystats.bin and reboot to do the same thing. (There should be an option for this in your Recovery module, if you're not running stock.)

So root users can calibrate without draining your battrey?

Michael A
03-13-2011, 12:49 AM
You guys are nuts ! Just plug your phone into the charger and go to bed .

iPeck
03-13-2011, 08:44 AM
You guys are nuts ! Just plug your phone into the charger and go to bed .

lol. There you go :p

Posted from my sweet Nexus One on GB via Hit'n'Yak

farhat_ali
03-17-2011, 09:17 AM
As posted by Mr. RinTinTigger, i tried caliberating the battery, but it did not work and it stills drain out withing half day with just push mail function-----no open and read is done

hawklan
06-24-2011, 01:00 AM
Hey gang, Just a heads-up:
I'm fooling around with a friend's Samsung t939 that shuts down way too fast.
My friend says the battery works fine in another phone. That made me curious.
The battery voltage is fine!!

Even when I play with or rm batterystats.bin the battery% is right out.
I've been wrestling with this one since February.
I've verified that the voltage being reported is genuine.
At 4.25v (full to the gills) 100%
4.1v 10%
4.011v 0%
SomewhereBelow3.86v Powering Off.
Back in February it was somewhere below 3.66v

When i charge it with the phone turned off, the firmware seems to report correctly (big blue battery on the screen shows mostly full, and then full.)

The battery's nominal voltage is 3.7.
The phone should auto shut-off at 3.2 or live dangerously to 3.1
but it's shutting down at now 3.8

I wonder if this is what's actually been soaking everyone's battery life and nobody's thought to check the actual voltages.
Thoughts? Suggestions? Where in the OS does the shutdown voltage get dictated? Is there another factor that controls when the phone shuts itself off?

Anyway.. I've tried flashing a few different roms, dunno what could possibly survive that.. Can't afford to replace, and kind of want to solve anyway. I'm hoping this stimulates the curiosity of some clever folks with a bit more intimate familiarity with the insides of the OS...

BarryA
08-16-2011, 11:17 PM
Tigger:

For your information, I followed your instructions that you posted online below . I followed your instructions to a tee. I regret to say that it killed my HTC HD2. (I think.I hope I am wrong though.) I repeated the instruction process (below) 3 times.

Upon making my 1st call after the calibration, my phone froze up and it made a weird buzzing sound. It would not stop not matter what I did, with the exception of pulling out the battery. When I pulled it out, and put it back in, the phone went totally dead. nothing lit up. I have not been able to boot it up since. Is there anything we can possiblly do?....Please help me fix my cell phone!

Barry Adler
email (direct): barryadler@verizon.net
---------------------------------------------------------------
Hey folks,

ive been asked a lot, how to calibrate your battery, to get more life out of it...

Calibrate your Battery

Calibrate the battery by completely draining it until the phone completely shuts itself off.
Turn the phone on again and let it shut itself off one more time.
Then charge your phone while it is off for over 8 hours.
This will fully charge the battery so that when the Android is turned on, it now sees the battery as full.

It is recommended to repeat this process at least one more time.

You should see a significant increase in your battery’s charge life.

Calibration of a battery can be done at any point and a maintenance calibration is recommended every month.


RECALIBRATION:

A recalibration is mostly needed, when dealing with different kernels (ROOT!). Most custom recovery images provide the option "battery stats wipe" under the menue "Wipe".

Here is how ya do it!

1. Enter Recovery Mode
2. do a full nandroid (or nandroid+ext) backup
3. Enter "Wipe"-Menue
4. do "Battery stats wipe"
5. reboot

Then you just take the steps from a bove to continue:

Calibrate the battery by completely draining it until the phone completely shuts itself off.
Turn the phone on again and let it shut itself off one more time.
Then charge your phone while it is off for over 8 hours.
This will fully charge the battery so that when the Android is turned on, it now sees the battery as full.

It is recommended to repeat this process at least one more time.

You should see a significant increase in your battery’s charge life.

Calibration of a battery can be done at any point and a maintenance calibration is recommended every month.


Tigger

:oilleak:[/QUOTE]

WERA689
08-17-2011, 01:05 AM
Sadly, Tigger hasn't been around in quite some time.

Which process did you follow? Are you rooted? I"m not sure how simply manipulating the battery or it's use files could cause what you're reporting here.

Is there any other information that may be pertinent to this failure?

alphawave7
08-18-2011, 12:03 AM
There are two processes occurring (or not occurring) when a battery discharges and recharges, electrical (electrons) and chemical (electron transference between media). I disapprove of Tigger's suggestion to restart a cell that is already exhausted, because it can irreversibly corrupt the chemical (Li-Ion, Li-Poly,etc.) and prevent it from recharging, essentially destroying the cell. Sometimes a cell that has experienced this can be 'jumpered' with another fully-charged cell to get enough juice to allow a recharge, but often they're lost causes. You need a new cell.